Add 84/54 and 90/21, Solve 1 30/54 + 4 6/21 as a fraction

Add 84/54 and 90/21

1^st number: 1 30/54, 2^nd number: 4 6/21

84/54 + 90/21 is 368/63.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
84/54 = 84 × 7/54 × 7 = 588/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
90/21 = 90 × 18/21 × 18 = 1620/378
Add the two like fractions:
588/378 + 1620/378 = 588 + 1620/378 = 2208/378
2208/378 simplified gives 368/63
So, 84/54 + 90/21 = 368/63
In mixed form: 553/63

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